- •Chapter 1 Introduction
- •1.1 Target audience
- •1.2 What is new in EJB 2.0
- •1.3 Acknowledgments
- •1.4 Organization
- •1.5 Document conventions
- •Chapter 2 Goals
- •2.1 Overall goals
- •2.2 EJB Releases 1.0 and 1.1
- •2.3 Goals for Release 2.0
- •Chapter 3 EJB Roles and Scenarios
- •3.1 EJB Roles
- •3.1.1 Enterprise Bean Provider
- •3.1.2 Application Assembler
- •3.1.3 Deployer
- •3.1.4 EJB Server Provider
- •3.1.5 EJB Container Provider
- •3.1.6 Persistence Manager Provider
- •3.1.7 System Administrator
- •3.2 Scenario: Development, assembly, and deployment
- •Chapter 4 Overview
- •4.1 Enterprise Beans as components
- •4.1.1 Component characteristics
- •4.1.2 Flexible component model
- •4.2 Enterprise JavaBeans contracts
- •4.2.1 Client-view contract
- •4.2.2 Component contract
- •4.2.4 Contracts summary
- •4.3 Session, entity, and message-driven objects
- •4.3.1 Session objects
- •4.3.2 Entity objects
- •4.3.3 Message-driven objects
- •4.4 Standard mapping to CORBA protocols
- •Chapter 5 Client View of a Session Bean
- •5.1 Overview
- •5.2 EJB Container
- •5.2.1 Locating a session bean’s home interface
- •5.2.2 What a container provides
- •5.3 Home interface
- •5.3.1 Creating a session object
- •5.3.2 Removing a session object
- •5.4 EJBObject
- •5.5 Session object identity
- •5.6 Client view of session object’s life cycle
- •5.7 Creating and using a session object
- •5.8 Object identity
- •5.8.1 Stateful session beans
- •5.8.2 Stateless session beans
- •5.8.3 getPrimaryKey()
- •5.9 Type narrowing
- •Chapter 6 Session Bean Component Contract
- •6.1 Overview
- •6.2 Goals
- •6.3 A container’s management of its working set
- •6.4 Conversational state
- •6.4.1 Instance passivation and conversational state
- •6.4.2 The effect of transaction rollback on conversational state
- •6.5 Protocol between a session bean instance and its container
- •6.5.1 The required SessionBean interface
- •6.5.2 The SessionContext interface
- •6.5.3 The optional SessionSynchronization interface
- •6.5.4 Business method delegation
- •6.5.5 Session bean’s ejbCreate<METHOD>(...) methods
- •6.5.6 Serializing session bean methods
- •6.5.7 Transaction context of session bean methods
- •6.6 STATEFUL Session Bean State Diagram
- •6.6.1 Operations allowed in the methods of a stateful session bean class
- •6.6.2 Dealing with exceptions
- •6.6.3 Missed ejbRemove() calls
- •6.6.4 Restrictions for transactions
- •6.7 Object interaction diagrams for a STATEFUL session bean
- •6.7.1 Notes
- •6.7.2 Creating a session object
- •6.7.3 Starting a transaction
- •6.7.4 Committing a transaction
- •6.7.5 Passivating and activating an instance between transactions
- •6.7.6 Removing a session object
- •6.8 Stateless session beans
- •6.8.1 Stateless session bean state diagram
- •6.8.2 Operations allowed in the methods of a stateless session bean class
- •6.8.3 Dealing with exceptions
- •6.9 Object interaction diagrams for a STATELESS session bean
- •6.9.1 Client-invoked create()
- •6.9.2 Business method invocation
- •6.9.3 Client-invoked remove()
- •6.9.4 Adding instance to the pool
- •6.10 The responsibilities of the bean provider
- •6.10.1 Classes and interfaces
- •6.10.2 Session bean class
- •6.10.3 ejbCreate<METHOD> methods
- •6.10.4 Business methods
- •6.10.5 Session bean’s remote interface
- •6.10.6 Session bean’s home interface
- •6.11 The responsibilities of the container provider
- •6.11.1 Generation of implementation classes
- •6.11.2 Session EJBHome class
- •6.11.3 Session EJBObject class
- •6.11.4 Handle classes
- •6.11.5 EJBMetaData class
- •6.11.6 Non-reentrant instances
- •6.11.7 Transaction scoping, security, exceptions
- •6.11.8 SessionContext
- •Chapter 7 Example Session Scenario
- •7.1 Overview
- •7.2 Inheritance relationship
- •7.2.1 What the session Bean provider is responsible for
- •7.2.2 Classes supplied by container provider
- •7.2.3 What the container provider is responsible for
- •Chapter 8 Client View of an Entity
- •8.1 Overview
- •8.2 EJB Container
- •8.2.1 Locating an entity bean’s home interface
- •8.2.2 What a container provides
- •8.3 Entity bean’s home interface
- •8.3.1 create methods
- •8.3.3 remove methods
- •8.3.4 home methods
- •8.4 Entity object’s life cycle
- •8.5 Primary key and object identity
- •8.6 Entity Bean’s remote interface
- •8.7 Entity bean’s handle
- •8.8 Entity home handles
- •8.9 Type narrowing of object references
- •Chapter 9 Entity Bean Component Contract for Container Managed Persistence
- •9.1 Overview
- •9.2 Data Independence between the Client View, the Entity Bean View, and the Persistence View
- •9.3 Container-managed entity persistence
- •9.3.1 Granularity of entity beans
- •9.4 The entity bean provider’s view of persistence
- •9.4.1 The entity bean provider’s programming contract
- •9.4.2 The entity bean provider’s view of persistent relationships
- •9.4.3 The view of dependent classes
- •9.4.4 The entity bean provider’s programming contract for dependent object classes
- •9.4.5 Semantics of dependent object classes
- •9.4.5.1 Semantics of assignment for instances of dependent object classes
- •9.4.6 Collections managed by the Persistence Manager
- •9.4.7 Dependent value classes
- •9.4.8 Non-persistent state
- •9.4.9 The relationship between the persistence view and the client view
- •9.4.10 Mapping data to a persistent store
- •9.4.11 Example
- •9.4.12 The Bean Provider’s view of the deployment descriptor
- •9.5 The entity bean component contract
- •9.5.1 Runtime execution model of entity beans
- •9.5.2 Relationships among the classes provided by the bean provider and persistence manager
- •9.6 Instance life cycle contract between the bean, the container, and the persistence manager
- •9.6.1 Instance life cycle
- •9.6.2 Bean Provider’s entity bean instance’s view
- •9.6.3 The Persistence Manager’s view
- •9.6.4 Container’s view
- •9.6.5 Operations allowed in the methods of the entity bean class
- •9.6.6 Finder method return type
- •9.6.7 Select methods
- •9.6.7.1 Single-object select methods
- •9.6.7.2 Multi-object select methods
- •9.6.8 Standard application exceptions for Entities
- •9.6.8.1 CreateException
- •9.6.8.2 DuplicateKeyException
- •9.6.8.3 FinderException
- •9.6.8.4 ObjectNotFoundException
- •9.6.8.5 RemoveException
- •9.6.9 Commit options
- •9.6.10 Concurrent access from multiple transactions
- •9.6.11 Non-reentrant and re-entrant instances
- •9.7 Responsibilities of the Enterprise Bean Provider
- •9.7.1 Classes and interfaces
- •9.7.2 Enterprise bean class
- •9.7.3 Dependent object classes
- •9.7.4 Dependent value classes
- •9.7.5 ejbCreate<METHOD> methods
- •9.7.6 ejbPostCreate<METHOD> methods
- •9.7.7 ejbHome<METHOD> methods
- •9.7.8 ejbSelect<METHOD> and ejbSelect<METHOD>InEntity methods
- •9.7.9 Business methods
- •9.7.10 Entity bean’s remote interface
- •9.7.11 Entity bean’s home interface
- •9.7.12 Entity bean’s primary key class
- •9.7.13 Entity bean’s deployment descriptor
- •9.8 The responsibilities of the Persistence Manager
- •9.8.1 Generation of implementation classes
- •9.8.2 Classes and interfaces
- •9.8.3 Enterprise bean class
- •9.8.4 Dependent object classes
- •9.8.5 ejbCreate<METHOD> methods
- •9.8.6 ejbPostCreate<METHOD> methods
- •9.8.7 ejbFind<METHOD> methods
- •9.8.8 ejbSelect<METHOD> and ejbSelect<METHOD>InEntity methods
- •9.9 The responsibilities of the Container Provider
- •9.9.1 Generation of implementation classes
- •9.9.2 Entity EJBHome class
- •9.9.3 Entity EJBObject class
- •9.9.4 Handle class
- •9.9.5 Home Handle class
- •9.9.6 Meta-data class
- •9.9.7 Instance’s re-entrance
- •9.9.8 Transaction scoping, security, exceptions
- •9.9.9 Implementation of object references
- •9.9.10 EntityContext
- •9.10 Primary Keys
- •9.10.1 primary key type
- •9.10.1.3 Special case: Unknown primary key class
- •9.11.1 Transaction context
- •9.11.2 Connection management
- •9.11.3 Connection management scenarios
- •9.11.3.1 Scenario: Pessimistic concurrency control
- •9.11.3.2 Scenario: Optimistic concurrency control
- •9.11.5 Container responsibilities
- •9.11.6 Persistence manager responsibilities
- •9.12 Object interaction diagrams
- •9.12.1 Notes
- •9.12.2 Creating an entity object
- •9.12.3 Passivating and activating an instance in a transaction
- •9.12.4 Committing a transaction
- •9.12.5 Starting the next transaction
- •9.12.6 Removing an entity object
- •9.12.7 Finding an entity object
- •9.12.8 Adding and removing an instance from the pool
- •Chapter 10 EJB QL: EJB Query Language for Container Managed Persistence Finder Methods
- •10.1 Overview
- •10.2.1 Abstract Schemas and Query Domains
- •10.2.1.1 Examples
- •10.2.2 Naming
- •10.2.3 Navigation Declarations and the FROM Clause
- •10.2.4 WHERE Clause and Conditional Expressions
- •10.2.4.1 Literals
- •10.2.4.3 Correlation Variables
- •10.2.4.4 Quoted Names
- •10.2.4.5 Path Expressions
- •10.2.4.6 Remote Interface Reference Expressions
- •10.2.4.7 Input Parameters
- •10.2.4.8 Conditional Expression Composition
- •10.2.4.9 Operators and Operator Precedence
- •10.2.4.10 Between Expression
- •10.2.4.11 In Expression
- •10.2.4.12 Like Expression
- •10.2.4.13 Null Comparison Expression
- •10.2.4.14 Finder Expression
- •10.2.5 SELECT Clause
- •10.2.6 Null Values
- •10.2.7 Equality
- •10.2.8 Restrictions
- •10.3 Examples
- •10.3.1 Simple Queries
- •10.3.2 Queries with Dependent Classes
- •10.3.3 Queries that refer to Other Entity Beans
- •10.3.4 Queries using input parameters
- •10.3.5 SELECT Queries
- •Chapter 11 Entity Bean Component Contract for Bean Managed Persistence
- •11.1 Overview of Bean Managed Entity Persistence
- •11.1.1 Granularity of entity beans
- •11.1.2 Entity Bean Provider’s view of persistence and relationships
- •11.1.3 Runtime execution model
- •11.1.4 Instance life cycle
- •11.1.5 The entity bean component contract
- •11.1.5.1 Entity bean instance’s view
- •11.1.5.2 Container’s view:
- •11.1.6 Operations allowed in the methods of the entity bean class
- •11.1.7 Caching of entity state and the ejbLoad and ejbStore methods
- •11.1.7.1 ejbLoad and ejbStore with the NotSupported transaction attribute
- •11.1.8 Finder method return type
- •11.1.9 Standard application exceptions for Entities
- •11.1.9.1 CreateException
- •11.1.9.2 DuplicateKeyException
- •11.1.9.3 FinderException
- •11.1.9.4 ObjectNotFoundException
- •11.1.9.5 RemoveException
- •11.1.10 Commit options
- •11.1.11 Concurrent access from multiple transactions
- •11.1.12 Non-reentrant and re-entrant instances
- •11.2 Responsibilities of the Enterprise Bean Provider
- •11.2.1 Classes and interfaces
- •11.2.2 Enterprise bean class
- •11.2.3 ejbCreate<METHOD> methods
- •11.2.4 ejbPostCreate<METHOD> methods
- •11.2.5 ejbFind methods
- •11.2.6 ejbHome<METHOD> methods.
- •11.2.7 Business methods
- •11.2.8 Entity bean’s remote interface
- •11.2.9 Entity bean’s home interface
- •11.2.10 Entity bean’s primary key class
- •11.3 The responsibilities of the Container Provider
- •11.3.1 Generation of implementation classes
- •11.3.2 Entity EJBHome class
- •11.3.3 Entity EJBObject class
- •11.3.4 Handle class
- •11.3.5 Home Handle class
- •11.3.6 Meta-data class
- •11.3.7 Instance’s re-entrance
- •11.3.8 Transaction scoping, security, exceptions
- •11.3.9 Implementation of object references
- •11.3.10 EntityContext
- •11.4 Object interaction diagrams
- •11.4.1 Notes
- •11.4.2 Creating an entity object
- •11.4.3 Passivating and activating an instance in a transaction
- •11.4.4 Committing a transaction
- •11.4.5 Starting the next transaction
- •11.4.6 Removing an entity object
- •11.4.7 Finding an entity object
- •11.4.8 Adding and removing an instance from the pool
- •Chapter 12 Example bean managed persistence entity scenario
- •12.1 Overview
- •12.2 Inheritance relationship
- •12.2.1 What the entity Bean Provider is responsible for
- •12.2.2 Classes supplied by Container Provider
- •12.2.3 What the container provider is responsible for
- •Chapter 13 EJB 1.1 Entity Bean Component Contract for Container Managed Persistence
- •13.1 EJB 1.1 Entity beans with container-managed persistence
- •13.1.2 ejbCreate, ejbPostCreate
- •13.1.3 ejbRemove
- •13.1.4 ejbLoad
- •13.1.5 ejbStore
- •13.1.7 home methods
- •13.1.8 create methods
- •13.1.9 primary key type
- •13.1.9.3 Special case: Unknown primary key class
- •13.2 Object interaction diagrams
- •13.2.1 Notes
- •13.2.2 Creating an entity object
- •13.2.3 Passivating and activating an instance in a transaction
- •13.2.4 Committing a transaction
- •13.2.5 Starting the next transaction
- •13.2.6 Removing an entity object
- •13.2.7 Finding an entity object
- •13.2.8 Adding and removing an instance from the pool
- •Chapter 14 Message-driven Bean Component Contract
- •14.1 Overview
- •14.2 Goals
- •14.3 Client view of a message-driven bean
- •14.4.1 The required MessageDrivenBean interface
- •14.4.2 The required javax.jms.MessageListener interface
- •14.4.3 The MessageDrivenContext interface
- •14.4.4 Message-driven bean’s ejbCreate() method
- •14.4.5 Serializing message-driven bean methods
- •14.4.6 Concurrency of message processing
- •14.4.7 Transaction context of message-driven bean methods
- •14.4.8 Message acknowledgement
- •14.4.9 Association of a message-driven bean with a destination
- •14.4.10 Dealing with exceptions
- •14.4.11 Missed ejbRemove() calls
- •14.5 Message-driven bean state diagram
- •14.5.1 Operations allowed in the methods of a message-driven bean class
- •14.6.1 Message receipt: onMessage method invocation
- •14.6.2 Adding instance to the pool
- •14.6.3 Removing instance from the pool
- •14.7 The responsibilities of the bean provider
- •14.7.1 Classes and interfaces
- •14.7.2 Message-driven bean class
- •14.7.3 ejbCreate method
- •14.7.4 onMessage method
- •14.7.5 ejbRemove method
- •14.8 The responsibilities of the container provider
- •14.8.1 Generation of implementation classes
- •14.8.2 Non-reentrant instances
- •14.8.3 Transaction scoping, security, exceptions
- •Chapter 15 Example Message-driven Bean Scenario
- •15.1 Overview
- •15.2 Inheritance relationship
- •15.2.1 What the message-driven Bean provider is responsible for
- •15.2.2 Classes supplied by container provider
- •15.2.3 What the container provider is responsible for
- •Chapter 16 Support for Transactions
- •16.1 Overview
- •16.1.1 Transactions
- •16.1.2 Transaction model
- •16.1.3 Relationship to JTA and JTS
- •16.2 Sample scenarios
- •16.2.1 Update of multiple databases
- •16.2.2 Messages sent or received over JMS sessions and update of multiple databases
- •16.2.3 Update of databases via multiple EJB Servers
- •16.2.4 Client-managed demarcation
- •16.2.5 Container-managed demarcation
- •16.2.6 Bean-managed demarcation
- •16.3 Use of resource manager local transactions as an optimization
- •16.3.1 Sample scenario: updates to a database by multiple beans in a local transaction
- •16.4 Bean Provider’s responsibilities
- •16.4.1 Bean-managed versus container-managed transaction demarcation
- •16.4.1.1 Non-transactional execution
- •16.4.2 Isolation levels
- •16.4.3 Enterprise beans using bean-managed transaction demarcation
- •16.4.3.1 getRollbackOnly() and setRollbackOnly() method
- •16.4.4 Enterprise beans using container-managed transaction demarcation
- •16.4.4.1 javax.ejb.SessionSynchronization interface
- •16.4.4.2 javax.ejb.EJBContext.setRollbackOnly() method
- •16.4.4.3 javax.ejb.EJBContext.getRollbackOnly() method
- •16.4.5 Use of JMS APIs in transactions
- •16.4.6 Local transaction optimization
- •16.4.7 Declaration in deployment descriptor
- •16.4.7.1 Transaction type
- •16.4.7.2 Local transaction optimization
- •16.5 Application Assembler’s responsibilities
- •16.5.1 Transaction attributes
- •16.6 Deployer’s responsibilities
- •16.7 Container Provider responsibilities
- •16.7.1 Bean-managed transaction demarcation
- •16.7.2 Container-managed transaction demarcation for Session and Entity Beans
- •16.7.2.1 NotSupported
- •16.7.2.2 Required
- •16.7.2.3 Supports
- •16.7.2.4 RequiresNew
- •16.7.2.5 Mandatory
- •16.7.2.6 Never
- •16.7.2.7 Transaction attribute summary
- •16.7.2.8 Handling of setRollbackOnly() method
- •16.7.2.9 Handling of getRollbackOnly() method
- •16.7.2.10 Handling of getUserTransaction() method
- •16.7.2.11 javax.ejb.SessionSynchronization callbacks
- •16.7.3 Container-managed transaction demarcation for Message-driven Beans
- •16.7.3.1 NotSupported
- •16.7.3.2 Required
- •16.7.3.3 Handling of setRollbackOnly() method
- •16.7.3.4 Handling of getRollbackOnly() method
- •16.7.3.5 Handling of getUserTransaction() method
- •16.7.4 Local transaction optimization
- •16.8 Access from multiple clients in the same transaction context
- •16.8.1 Transaction “diamond” scenario with an entity object
- •16.8.2 Container Provider’s responsibilities
- •16.8.3 Bean Provider’s responsibilities
- •16.8.4 Application Assembler and Deployer’s responsibilities
- •16.8.5 Transaction diamonds involving session objects
- •Chapter 17 Exception handling
- •17.1 Overview and Concepts
- •17.1.1 Application exceptions
- •17.1.2 Goals for exception handling
- •17.2 Bean Provider’s responsibilities
- •17.2.1 Application exceptions
- •17.2.2 System exceptions
- •17.2.2.1 javax.ejb.NoSuchEntityException
- •17.3 Container Provider responsibilities
- •17.3.1 Exceptions from a session or entity bean’s business methods
- •17.3.2 Exceptions from message-driven bean methods
- •17.3.3 Exceptions from container-invoked callbacks
- •17.3.4 javax.ejb.NoSuchEntityException
- •17.3.5 Non-existing session object
- •17.3.6 Exceptions from the management of container-managed transactions
- •17.3.7 Release of resources
- •17.3.8 Support for deprecated use of java.rmi.RemoteException
- •17.4 Client’s view of exceptions
- •17.4.1 Application exception
- •17.4.2 java.rmi.RemoteException
- •17.4.2.1 javax.transaction.TransactionRolledbackException
- •17.4.2.2 javax.transaction.TransactionRequiredException
- •17.4.2.3 java.rmi.NoSuchObjectException
- •17.5 System Administrator’s responsibilities
- •17.6 Differences from EJB 1.0
- •18.1 Support for distribution
- •18.1.1 Client-side objects in distributed environment
- •18.2 Interoperability overview
- •18.2.1 Interoperability goals
- •18.3 Interoperability Scenarios
- •18.3.1 Interactions between web containers and EJB containers for e-commerce applications
- •18.3.3 Interactions between two EJB containers in an enterprise’s intranet
- •18.3.4 Interactions between web containers and EJB containers for intranet applications
- •18.3.5 Overview of interoperability requirements
- •18.4 Remote Invocation Interoperability
- •18.4.1 Mapping Java Remote Interfaces to IDL
- •18.4.2 Mapping value objects to IDL
- •18.4.3 Mapping of system exceptions
- •18.4.4 Obtaining stub and value classes
- •18.5 Transaction interoperability
- •18.5.1 Transaction interoperability requirements
- •18.5.1.1 Transaction context wire format
- •18.5.1.2 Two-phase commit protocol
- •18.5.1.3 Transactional attributes of enterprise bean references
- •18.5.1.4 Exception handling behavior
- •18.5.2 Interoperating with containers that do not implement transaction interoperability
- •18.5.2.1 Client container requirements
- •18.5.2.2 EJB container requirements
- •18.5.2.2.1 Requirements for EJB containers supporting transaction interoperability
- •18.5.2.2.2 Requirements for EJB containers not supporting transaction interoperability
- •18.6 Naming Interoperability
- •18.7 Security Interoperability
- •18.7.1 Introduction
- •18.7.1.1 Trust relationships between containers, principal propagation
- •18.7.1.2 Application Client Authentication
- •18.7.2 Securing EJB invocations
- •18.7.2.1 Initiating a secure connection
- •18.7.2.2 Propagating principals and authentication data in IIOP messages
- •18.7.2.4 Run time behavior
- •Chapter 19 Enterprise bean environment
- •19.1 Overview
- •19.2 Enterprise bean’s environment as a JNDI naming context
- •19.2.1 Bean Provider’s responsibilities
- •19.2.1.1 Access to enterprise bean’s environment
- •19.2.1.2 Declaration of environment entries
- •19.2.2 Application Assembler’s responsibility
- •19.2.3 Deployer’s responsibility
- •19.2.4 Container Provider responsibility
- •19.3 EJB references
- •19.3.1 Bean Provider’s responsibilities
- •19.3.1.1 EJB reference programming interfaces
- •19.3.1.2 Declaration of EJB references in deployment descriptor
- •19.3.2 Application Assembler’s responsibilities
- •19.3.3 Deployer’s responsibility
- •19.3.4 Container Provider’s responsibility
- •19.4 Resource manager connection factory references
- •19.4.1 Bean Provider’s responsibilities
- •19.4.1.1 Programming interfaces for resource manager connection factory references
- •19.4.1.2 Declaration of resource manager connection factory references in deployment descriptor
- •19.4.1.3 Standard resource manager connection factory types
- •19.4.2 Deployer’s responsibility
- •19.4.3 Container provider responsibility
- •19.4.4 System Administrator’s responsibility
- •19.5 Resource environment references
- •19.5.1 Bean Provider’s responsibilities
- •19.5.1.1 Resource environment reference programming interfaces
- •19.5.1.2 Declaration of resource environment references in deployment descriptor
- •19.5.2 Deployer’s responsibility
- •19.5.3 Container Provider’s responsibility
- •19.6 Deprecated EJBContext.getEnvironment() method
- •19.7 UserTransaction interface
- •Chapter 20 Security management
- •20.1 Overview
- •20.2 Bean Provider’s responsibilities
- •20.2.1 Invocation of other enterprise beans
- •20.2.2 Resource access
- •20.2.3 Access of underlying OS resources
- •20.2.4 Programming style recommendations
- •20.2.5 Programmatic access to caller’s security context
- •20.2.5.1 Use of getCallerPrincipal()
- •20.2.5.2 Use of isCallerInRole(String roleName)
- •20.2.5.3 Declaration of security roles referenced from the bean’s code
- •20.3 Application Assembler’s responsibilities
- •20.3.1 Security roles
- •20.3.2 Method permissions
- •20.3.3 Linking security role references to security roles
- •20.3.4.1 RunAs
- •20.4 Deployer’s responsibilities
- •20.4.1 Security domain and principal realm assignment
- •20.4.2 Assignment of security roles
- •20.4.3 Principal delegation
- •20.4.4 Security management of resource access
- •20.4.5 General notes on deployment descriptor processing
- •20.5 EJB Client Responsibilities
- •20.6 EJB Container Provider’s responsibilities
- •20.6.1 Deployment tools
- •20.6.2 Security domain(s)
- •20.6.3 Security mechanisms
- •20.6.4 Passing principals on EJB calls
- •20.6.5 Security methods in javax.ejbEJBContext
- •20.6.6 Secure access to resource managers
- •20.6.7 Principal mapping
- •20.6.8 System principal
- •20.6.9 Runtime security enforcement
- •20.6.10 Audit trail
- •20.7 System Administrator’s responsibilities
- •20.7.1 Security domain administration
- •20.7.2 Principal mapping
- •20.7.3 Audit trail review
- •Chapter 21 Deployment descriptor
- •21.1 Overview
- •21.2 Bean Provider’s responsibilities
- •21.3 Application Assembler’s responsibility
- •21.4 Container Provider’s responsibilities
- •21.5 Deployment descriptor DTD
- •Chapter 22 Ejb-jar file
- •22.1 Overview
- •22.2 Deployment descriptor
- •22.5 Deprecated in EJB 1.1
- •22.5.1 ejb-jar Manifest
- •22.5.2 Serialized deployment descriptor JavaBeans™ components
- •Chapter 23 Runtime environment
- •23.1 Bean Provider’s responsibilities
- •23.1.1 APIs provided by Container
- •23.1.2 Programming restrictions
- •23.2 Container Provider’s responsibility
- •23.2.1 Java 2 APIs requirements
- •23.2.2 EJB 2.0 requirements
- •23.2.3 JNDI 1.2 requirements
- •23.2.4 JTA 1.0.1 requirements
- •23.2.6 JMS 1.0.2 requirements
- •23.2.7 Argument passing semantics
- •Chapter 24 Responsibilities of EJB Roles
- •24.1 Bean Provider’s responsibilities
- •24.1.1 API requirements
- •24.1.2 Packaging requirements
- •24.2 Application Assembler’s responsibilities
- •24.3 EJB Container Provider’s responsibilities
- •24.4 Deployer’s responsibilities
- •24.5 System Administrator’s responsibilities
- •24.6 Client Programmer’s responsibilities
- •Chapter 25 Enterprise JavaBeans™ API Reference
- •package javax.ejb
- •package javax.ejb.deployment
- •Chapter 26 Related documents
- •Appendix A Features deferred to future releases
- •Appendix B EJB 1.1 Deployment descriptor
- •B.1 Overview
- •B.2 Bean Provider’s responsibilities
- •B.3 Application Assembler’s responsibility
- •B.4 Container Provider’s responsibilities
- •B.5 Deployment descriptor DTD
- •B.6 Deployment descriptor example
- •Appendix C EJB 1.1 Runtime environment
- •C.1 EJB 1.1 Bean Provider’s responsibilities
- •C.1.1 APIs provided by EJB 1.1 Container
- •C.1.2 Programming restrictions
- •C.2 EJB 1.1 Container Provider’s responsibility
- •C.2.1 Java 2 Platform, Standard Edition, v 1.2 (J2SE) APIs requirements
- •C.2.2 EJB 1.1 requirements
- •C.2.3 JNDI 1.2 requirements
- •C.2.4 JTA 1.0.1 requirements
- •C.2.5 JDBC™ 2.0 extension requirements
- •C.2.6 Argument passing semantics
- •Appendix D Frequently asked questions
- •D.1 Client-demarcated transactions
- •D.2 Container managed persistence
- •D.3 Inheritance
- •D.4 Entities and relationships
- •D.5 How to obtain database connections
- •D.6 Session beans and primary key
- •D.7 Copying of parameters required for EJB calls within the same JVM
- •Appendix E Revision History
- •E.1 Version 0.1
- •E.2 Version 0.2
- •E.3 Version 0.3
- •E.4 Version 0.4
- •E.5 Version 0.5
- •E.6 Version 0.6
- •E.7 Version 0.7
- •E.8 Participant Draft
- •E.9 Public Draft
Sun Microsystems Inc
EJBObject |
Enterprise JavaBeans 2.0, Public Draft |
Client View of a Session Bean |
5.4 EJBObject
A client never directly accesses instances of the session bean’s class. A client always uses the session bean’s remote interface to access a session bean’s instance. The class that implements the session bean’s remote interface is provided by the container; its instances are called session EJBObjects.
A session EJBObject supports:
•The business logic methods of the object. The session EJBObject delegates invocation of a business method to the session bean instance.
•The methods of the javax.ejb.EJBObject interface. These methods allow the client to:
•Get the session object’s home interface.
•Get the session object’s handle.
•Test if the session object is identical with another session object.
•Remove the session object.
The implementation of the methods defined in the javax.ejb.EJBObject interface is provided by the container. They are not delegated to the instances of the session bean class.
5.5 Session object identity
Session objects are intended to be private resources used only by the client that created them. For this reason, session objects, from the client’s perspective, appear anonymous. In contrast to entity objects, which expose their identity as a primary key, session objects hide their identity. As a result, the EJBObject.getPrimaryKey() and EJBHome.remove(Object primaryKey) methods result in a java.rmi.RemoteException if called on a session bean. If the EJBMetaData.getPrimaryKeyClass()method is invoked on a EJBMetaData object for a Session bean, the method throws the java.lang.RuntimeException.
Since all session objects hide their identity, there is no need to provide a finder for them. The home interface of a session bean must not define any finder methods.
A session object handle can be held beyond the life of a client process by serializing the handle to persistent store. When the handle is later deserialized, the session object it returns will work as long as the session object still exists on the server. (An earlier timeout or server crash may have destroyed the session object.)
The client code must use the javax.rmi.PortableRemoteObject.narrow(...)method to convert the result of the getEJBObject() method invoked on a handle to the remote interface type.
A handle is not a capability, in the security sense, that would automatically grant its holder the right to invoke methods on the object. When a reference to a session object is obtained from a handle, and then a method on the session object is invoked, the container performs the usual access checks based on the caller’s principal.
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Sun Microsystems Inc.
Client View of a Session Bean |
Enterprise JavaBeans 2.0, Public Draft |
Client view of session object’s life cycle |
5.6 Client view of session object’s life cycle
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From a client point of view, the life cycle of a session object is illustrated below. |
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Figure 3 |
Lifecycle of a session object. |
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client’s method on reference
A session object does not exist until it is created. When a client creates a session object, the client has a reference to the newly created session object’s remote interface.
A client that has a reference to a session object can then do any of the following:
•Invoke business methods defined in the session object’s remote interface.
•Get a reference to the session object’s home interface.
•Get a handle for the session object.
•Pass the reference as a parameter or return value within the scope of the client.
•Remove the session object. A container may also remove the session object automatically when the session object’s lifetime expires.
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Creating and using a session object |
Enterprise JavaBeans 2.0, Public Draft |
Client View of a Session Bean |
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It is invalid to reference a session object that does not exist. Attempted invocations on a session object |
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that does not exist result in java.rmi.NoSuchObjectException. |
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5.7 Creating and using a session object |
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An example of the session bean runtime objects is illustrated by the following diagram: |
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Figure 4 |
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Session Bean Example Objects |
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container |
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Cart |
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CartBean |
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CartHome |
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A client creates a Cart session object (which provides a shopping service) using a create<METHOD>(...) method of the Cart’s home interface. The client then uses this session object to fill the cart with items and to purchase its contents.
Suppose that the end-user wishes to start the shopping session, suspend the shopping session temporarily for a day or two, and later complete the session. The client might implement this feature by getting the session object’s handle, saving the serialized handle in persistent storage, then using it later to reestablish access to the original Cart.
For the following example, we start by looking up the Cart’s home interface in JNDI. We then use the home interface to create a Cart session object and add a few items to it:
CartHome cartHome = (CartHome)javax.rmi.PortableRemoteObject.narrow( initialContext.lookup(...), CartHome.class);
Cart cart = cartHome.createLargeCart(...); cart.addItem(66);
cart.addItem(22);
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